[1] The B-side "Poppy Nogood and the Phantom Band" is a saxophone-based drone piece featuring tape loops and edits, drawing on Riley's all-night improvisatory performances in the 1960s.

Jazz pianist Bill Evans, one of Riley's piano "heroes",[11] had utilized overdubbing on his classic album Conversations with Myself from four years earlier.

[1] The piece moves through several sections; following the opening theme and introduction of "placid chords," Riley introduces "an explosion, a procession of right-hand lines that flutter and pirouette over the pulsing rhythmic patterns.

[10] A note on the album explains that "The spatially separated mirror images were adapted for studio recording by Glen Kolotkin and resemble the sound Terry gets in his all-night concerts.

"[15] The original LP jacket includes a idealistic poem on the back cover, written by Riley, which depicts a world in which the Pentagon is "turned on its side and painted purple, yellow & green within a plainly psychedelic environment" and "the concept of work was forgotten.

[7] Writing for The Village Voice, critic Robert Christgau opined positively that the "title side of this has to be a fair approximation of the music of the spheres.

[19] The album's title track is also featured in the video game Grand Theft Auto IV on the in-game radio station "The Journey."

In 2009 the track "Poppy Nogood and the Phantom Band" was featured in the BBC documentary Prog Rock Britannia: An Observation in Three Movements.